Device for local electric-spark layering of metals and alloys by means of rotating electrode

ABSTRACT

A method is provided for local electric-spark layering of metals and alloys by means of a rotating electrode, wherein a layering electrode of rod shape and with a diameter smaller than 2 mm is rotated around its axis, said electrode being maintained from the surface to be layered at a distance in function of the disruptive voltage and the current, wherein the electrical impulses have at idle running 15 to 600 Volts and duration of from 1 to 10 microseconds. A device for accomplishing this method is also provided.

United States Patent 1191 1111 3,832,514 Antonov 1 1 Aug. 27, 1974 [54]DEVI E FOR LOCAL ELECTRIC-SPARK 3,277,266 10/1966 Blaszkowski 219/76 QND3,277,267 10/1966 Blaszkowski.. 219/76 LAYERING 0F METALS ALOLOYS BY3,446,932 5/1969 BCIOpltOV 204/192 MEANS OF ROTATING ELECT DE 3,546,09112/1970 Rossner 204/298 Inventor: Bogomil Totev Antonov, Sofia,

. Bulgaria Assignee: DSO IZOT Sofia, Bulgaria Filed: Nov. 27, 1972 Appl.N6; 309,900

Foreign Application Priority Data Nov. 27, 1971 Bulgaria 19113 US. Cl.219/76, 204/298 Int. Cl B23k 9/04, C23c 15/00 Field of Search 204/192,298; 219/76, 77

References Cited UNITED STATES PATENTS Rossner 219/76 Primary ExaminerT.Tufariello Attorney, Agent, or Firm-Armstrong, Nikaido & Wegner'ABSTRACT A method is provided for local electric-spark layering ofmetals and alloys by means of a rotating electrode, wherein a layeringelectrode of rod shape and with a diameter smaller than 2 mm is rotatedaround its axis, said electrode being maintained from the surface to belayered at a distance in function of the disruptive voltage and thecurrent, wherein the electrical impulses have at idle running 15 to 600Volts and duration of from 1 to 10 microseconds. A device foraccomplishing this method is also provided.

8 Claims, 7 Drawing Figures DEVICE FOR LOCAL ELECTRIC-SPARK LAYERING OFMETALS AND ALLOYS BY IVIEANS OF ROTATING ELECTRODE BACKGROUND OF THEINVENTION The present invention relates to a method and a device forlocal electric-spark layering of metals and alloys by means of arotating electrode.

Some methods are known for electric-spark layering of metals and alloysupon contact and layering on other surfaces by means of a electrodevibrating perpendicularly to the surface and moving on it.

A method is also known for electric-spark layering of metals and alloysby means of a rotating electrode, representing a disk or a brush made ofthe metal which is layered with radially disposed wires.

The coatings obtained according to the aforementioned methods lackuniform thickness, and suffer from the limitation of the layered areaand a sufficient density. The results obtained are not reproducible anddepend to a great extent to'the skill of the operator. Accordingly,these methods are generally unsuited for uniform coatings on local areaswhich is necessary, for example, in the fields of electronics and radioengineering, which make use of relatively expensive manual devices.

Through the present invention, the aforementioned disadvantages of theknown methods and devices for electric-spark layering of metals andalloys are obviated.

DESCRIPTION OF THE INVENTION According to the present invention, thecoating is layered by means of the butt of the layering electrode, whichis rodshape and having a diameter of less than 2 mm. This isaccomplished by rotating the butt around its axis, supported at anoptimal distance from the layered portion in function of the disruptivevoltage and the current. The electrical impulses are of about 15 toabout 600 volts (idle running) with a duration of l to microseconds.

If the width of the layer is larger than the diameter of the layeringelectrode, for obtaining ringshaped layers as well as layers withdesirable shape and dimensions, the motion of the electrode must beplanetary of controllable speed and radius. In this case, it may benecessary that the layered portion must be moved planary.

The device for the implementation of the method of the invention,contains a layering electrode, the layered portion, a generator forcurrent impulses, a current supplying device, and an electromotor forthe rotation of the layering electrode. The layering electrode isrodshaped and under 2 mm of diameter, and is fastened to the layeringhead and rotated around its axis by an incorporated electromotor in thesaid head, which is moved with the head axially by means of a followingup system. This assures an optimal distance between the butt (contactpoint) of the layering electrode and the fastened on the table layeredportion. Both are supplied by the electrical impulses generator.

The generator of the electrical impulses should be connected with thelayering electrode by means of a mercury current supplying device andthe electrical impulses should be of controllable paramaters: idlerunning voltage from 15 to 600 Volts and the duration of the impulsesfrom I to 10 microsec.

The device should posses a mechanism ensuring a planetary motion of therotating and layering electrode with controllable speed and radius toobtain coatings with a width larger than the diameter of the layeringelectrode or for obtaining ringshaped and other coatings. For the samescope the layering device must be equipped with a mechanism for planarmoving of the table and the layered detail fastened on it by aprogramming facility.

The method and the device of the invention for electric-spark layeringof metals and alloys, ensures the obtaining of local high quality densecoatings in a programming cycle and automatic maintenance of the optimaltechnological parameters of the regime and high productivity.

The method and the device, according to the invention, for the electricspark layering of metals and alloys will be illustrated better in termsof the drawings, wherein:

FIG. 1 represents the principles of the local electricspark layeringaccording to the invention;

FIG. 2 represents the principles of the local electricspark layering bymeans of a rotating and planetary moving layering electrode at a radiusof the planetary motion equal to the radius of the electrode;

FIG. 3 represents the principles of the local electricspark layering ofringshaped coatings by means of the rotating and planetary movinglayering electrode at a radius of the planetary motion larger than theradius of the layering electrode;

FIG. 4 represents the principles of the local electricspark layering ofcoatings, with a width multiply exceeding the diameter of the layeringelectrode.

FIG. 5 represents the block diagram of the device for localelectric-spark layering of metals and alloys by means of a rotatingelectrode;

FIG. 6 represents the schematic representation of the layering head withthe incorporated in it mechanism of the planetary motion of the layeringelectrode;

FIG. 7 represents the schematic representation of a second version ofthe mechanism of the planetary motion of the layering electrode.

FIG. 1 shows that the layering rodshaped electrode 1 made by the layered.metal or alloy performs rotational movement around its axis and itsbutt (contact point) is at a definite distance from the surface of thedetail (part) 2. The electrical impulse generator 4 supplies thelayering electrode 1 and the layered detail 2 and as a result of theelectric-spark layering on the surface of the latter (the detail) alocal coating is formed with a form of a round platform 3, anddimensions quite near to the diameter of the layering electrode 1.

FIG. 2 shows the principle of the local electric-spark layeringaccording to the invention, by means of a electrode rotating around itsaxis and planetary moving 1, at a radius of the planetary motion equalto the radius of the layering electrode 1. The platform shaped coating 3is fo a diameter equal twice the diameter of the layering electrode 1.

FIG. 3 shows the principle of the local electric-spark layering ofcoatings by means of a rotating around its axis and planetary movinglayering electrode 1, with a radius of the planetary motion larger thanthe radius of the layering electrode, at which conditions the coating 3has a form of ringshaped band.

FIG. 4 shows the principle of the local electric-spark layering of acoating, according to the invention, the width of which (the coating)substantially exceeding the diameter of the layering electrode 1, andpossessing a desirable shape, obtained combining the planetary motion ofthe rotating layering electrode 1 and the planary displacement of thelayered detail 2 by the programming facility 15 with the servomechanisms5 and 6.

FIG. 5 shows the block diagram of the electric-spark layering devicewith the rotating layering electrode, according to the invention, which(the device) consists of a layering head body 7, in which on ballguidance leads axially the layering head 8, upon which is fastened theelectromotor 12, to which is clamped the layering rodshaped electrode 1made by the layered metal or alloy. On the table 16 is fastened thelayered portion 2. The layering head 8 is displaced vertically by meansof the electromotor 10 and the gear mechanism 11, both guided by anelectronic following up system, in such a manner that between thesurface of the layered detail and the butt of the layering electrode adefinite optimal gap (clearance) is maintained. The speed of theelectromotor 12 is controlled by means of the device 13 in dependence ofthe dimensions (size) of the layering electrode 1. The electricalimpulse generator 4 is coupled to the mercury current supplying device14 and the table 16 upon which is fastened the layered portion 2. Bymeans of the programming facility 15 and the servomechanisms 5 and 6,the table 16 and the fastened on it detail 2 is displaced and planaryturned.

FIG. 6 shows one of the possible versions of the device for planetarydisplacement of the layering electrode 1, incorporated in the layeringhead. From the figure it appears that it (the device) contains acontrollable electromotor 17 with a gear mechanism 18, under which (thegear mechanism) is disposed a handle carrier (clamp) with a radial(block) bearing 19, and on the shaft (axle) of the gear mechanism 18 isfastened an inverted cup 20, in which on guidances is fastened a tailpiece (shank) 22 connected to the adjusting screw 21. The tail piece(shank) 22 is carrying the electromotor 12 with the layering electrode1.

FIG. 7 shows another version of the device for planetary motion of thelayering electrode 1. From the figure it appears that the devicecontains a controllable motor 23 with a gear mechanism 24, both disposedunder the table 16 with the layered detail 2. Above the gear mechanism24, on the shaft is fastened the framework 25, in which is disposed thebody 26 with the finger 27, which axis coincides with the axis of thelayering electrode 1, and the said body is led on guidances in theframework and is fixed by a screw 28. The horizontally disposedconnecting rod 29, carrying the body 7 of the layering head 8 isconnected through a bearing upon the said finger 27 and a second finger30, fastened upon the horizontal plate 31, led on guidance 32.

The following examples further illustrate the invention:

LOCAL ELECTRIC SPARK LAYERING (FIG. 5)

The layering electrode 1 rotating around its axis by means of theelectromotor 12 is maintained at a optimal distance from the layereddetail 2 by following up system 9 with the motor 10 and the gearmechanism 1 l.

The said distance is a function of the disruptive voltage and thecurrent. The electric impulse generator 4 is coupled to the layereddetail 2 directly and to the layering electrode 1 by means of themercury current sup plying device 14. The coating on the detail 2 isobtained as a result of the spark discharges. The quality of the coatingfor the given materials depends of the parameters of the electricimpulses, the speed of the rotation of the layering electrode and theduration of the layering process, as well as of the interelectrode gap(distance), maintained by the following up system 9. At the appropriatedisplacement of the table 16 with the layered detail fixed on it by themechanisms 5 and6,

controlled by the programming facility, can be obtained coatings withthe desired shape and width, near to the diameter of the.layeringelectrode 1.

PLANETARY MOTION OF THE LAYERING ELECTRODE (FIG. 6)

The controllable motor 17, by means of the gear mechanism 18 drives thecup 20, which turns the tail piece 22 and the layering electrode 1 withthe rotational motor 12. By means of the screw 21 the tail piece 22 isadjusted and fixed, which determines the appropriate radius of theplanetary motion. The speed of the latter (planetary motion) iscontrolled by the motor 17. Making use of the said device coatings 3could be ob tained, having larger width than the diameter of thelayering electrode 1 and desirable shapes, as shown in FIGS. 2, 3 and 4,combining the planetary motion with the respective planar displacementof the table 16 by the programming facility 15 and the servomechanisms 5and 6.

PLANETARY DISPLACEMENT OF THE LAYERING ELECTRODE (FIG. 7)

The controllable motor 23 by means of the gear mechanism 24 drives thebody 25 with the incorporated body 26 with the finger 27, which fingermakes circular motion of radius preselected by the screw 28. Theconnecting rod 29 driven by the finger 27, drives the body 7 of thelayering head 8, which with the layering electrode together performsplanetary motion. This device realizes the planetary displacements ofthe layering electrode 1 at substantially larger radii.

What is claimed is: 1

l. A device for spark layering metals and alloys onto a substrate, saiddevice comprising:

a. a rod shaped layering electrode;

b. first means for rotating said layering electrode about itslongitudinal axis;

c. second means for moving said layering electrode in a planetary motionabout its longitudinal axis;

d. table means for supporting said substrate under said electrode;

e. means for maintaining said electrode a predetermined distance fromsaid table means wherein said distance is a function of the voltage andcurrent applied to the electrode.

2. The device of claim 1 wherein said table means includes third meansfor moving said table means relative to said electrode.

3. The device of claim 1 wherein the diameter of said layering electrodeis less than 2 mm.

4. The device of claim 2 wherein said first means comprises a rotationalmotor coupled to said layering electrode.

nisms.

7. The device of claim 1 wherein said first means comprises a rotationalmotor. I

8. The device of claim 6 wherein said second means comprises:

a. a first body coupled to said first means;

b. a connecting rod coupled to said first body;

0. finger means coupled to said connecting rod; and,

d. drive means for driving said finger means in a circular motion.

1. A device for spark layering metals and alloys onto a substrate, saiddevice comprising: a. a rod shaped layering electrode; b. first meansfor rotating said layering electrode about its longitudinal axis; c.second means for moving said layering electrode in a planetary motionabout its longitudinal axis; d. table means for supporting saidsubstrate under said electrode; e. means for maintaining said electrodea predetermined distance from said table means wherein said distance isa function of the voltage and current applied to the electrode.
 2. Thedevice of claim 1 wherein said table means includes third means formoving said table means relative to said electrode.
 3. The device ofclaim 1 wherein the diameter of said layering electrode is less than 2mm.
 4. The device of claim 2 wherein said first means comprises arotational motor coupled to said layering electrode.
 5. The device ofclaim 4 wherein said second means comprises: a. a shank coupled to saidmotor; b. cup means coupled to said shank; c. gear means coupled to saidcup through block bearing means; and, d. motor means for driving saidgear means.
 6. The device of claim 5 wherein said third means comprises:a. servomechanisms coupled to said table means; and, b. a program meanscoupled to said servomechanisms.
 7. The device of claim 1 wherein saidfirst means comprises a rotational motor.
 8. The device of claim 6wherein said second means comprises: a. a first body coupled to saidfirst means; b. a connecting rod coupled to said first body; c. fingermeans coupled to said connecting rod; and, d. drive means for drivingsaid finger means in a circular motion.